Individual differences in relational body image: Within-person variability predicts maladaptive trait body image.

Findings have been mixed as to whether individual differences in within-person variability in body image predict maladaptive body image and eating behaviors. The current study aimed to resolve this ambiguity by addressing limitations of past research. First, we measured within-person variability in body image across the context-sensitive domain of relationships. Second, we incorporated the latest statistical methods to increase the robustness of the results. Online, 189 female-identified undergraduates completed seven baseline measures of trait body image. At least three days later, in-lab, participants were guided to generate a list of the most important people in their lives (i.e., friends, family members, close others) using egocentric network methods. Participants then completed a set of three relationship-specific measures in which they reported on their typical body image with 10 people from their list, one by one. Multiverse analysis tested the hypothesis that, across combinations of measures, within-person variability in relational body image would positively predict indicators of maladaptive body image. In 84 regression analyses, permutation testing supported our overall hypothesis (p = .006); however, results varied across different model specifications. Results provide further evidence for the predictive power of within-person variability in body image and yield valuable methodological and statistical recommendations.